1. Field of the Invention
The present invention relates to a lens barrel, a camera body, and an imaging device that have a manual focus function.
2. Description of the Related Art
A single lens reflex camera for an expert or the like has a manual focus function that allows a user to manually adjust a focus. A camera having a manual focus function includes an operation ring that is operated by a user and a drive unit that moves a focus lens according to the rotation angle or the angular position of the operation ring.
JP5028945B (corresponding to U.S. Pat. No. 7,969,672) and JP2013-7837A (corresponding to U.S. Pat. Nos. 9,013,607 and 9,235,026) disclose cameras that have a first manual focus mode and a second manual focus mode. In the first manual focus mode, a focus lens is moved according to the rotation angle of an operation ring. In the second manual focus mode, the focus lens is moved according to the angular position of the operation ring. Each of the cameras disclosed in JP5028945B and JP2013-7837A can adjust a focus by appropriately switching the first manual focus mode and the second manual focus mode.
Specifically, each of the cameras disclosed in JP5028945B and JP2013-7837A includes an operation ring that is mounted so as to be movable between a first position and a second position in the direction of an optical axis of an imaging optical system. The operation ring can endlessly rotate in a case in which the operation ring is positioned at the first position. The operation ring can rotate about the optical axis in a limited angular range in a case in which the operation ring is positioned at the second position.
Further, each of the cameras disclosed in JP5028945B and JP2013-7837A includes a first detection unit, a second detection unit, a drive unit, and a control unit. The first detection unit detects the rotation angle of the operation ring. The second detection unit detects the angular position of the operation ring. The drive unit moves the focus lens. The control unit controls the first detection unit, the second detection unit, and the drive unit. Specifically, the control unit moves the focus lens according to the rotation angle of the operation ring in a case in which the operation ring is positioned at the first position. The control unit moves the focus lens according to the angular position of the operation ring in a case in which the operation ring is positioned at the second position. In the camera disclosed in JP2013-7837A, the operation ring is provided with a distance scale and a lens barrel body is provided with an index. In the event that the angular position of the operation ring positioned at the second position is changed, the control unit moves the focus lens to a position where an imaging distance corresponding to the distance scale of a position indicated by the index is obtained.
In a case in which a user determines an imaging distance through eye measurement or the like and takes an image, it is easy to use the second manual focus mode in which the focus lens is moved according to the angular position of the operation ring. Ina case in which a user finely adjusts an imaging distance little by little while checking an image, it is easy to use the first manual focus mode in which the focus lens is moved according to the rotation angle of the operation ring.
However, in the cameras disclosed in JP5028945B and JP2013-7837A, a mode is switched between the first manual focus mode and the second manual focus mode by the sliding of the operation ring in the direction of the optical axis. For this reason, labor is required for a switching operation. There is a possibility that an imaging timing may be missed while the switching operation is performed.